Anti-thrombogenic catheter and method

Abstract

A medical catheter assembly is provided including an inner catheter member, where that inner catheter member includes a plurality of inner catheter lumens, and an outer sheath with at least one patent sheath lumen. The inner catheter is slidably disposed through a length of the at least one patent sheath lumen in a manner providing a substantially sealing contact between an exterior surface of the inner catheter and an inward surface of the at least one patent sheath lumen. A first of the plurality of inner catheter lumens includes a plurality of apertures to the exterior surface of the inner catheter, and a second of the plurality of inner catheter lumens includes at least one distal end-tip opening. A method of using the assembly is also provided.

The invention claimed is: 
     
       1. A method for installing a catheter assembly having an inner catheter member comprising a plurality of inner catheter lumens, and an outer sheath comprising at least one patent sheath lumen; where the inner catheter is slidably disposed through a length of the at least one patent sheath lumen in a manner providing a substantially sealing contact between an exterior surface of the inner catheter and an inward surface of the at least one patent sheath lumen; a first of the plurality of inner catheter lumens comprising a plurality of apertures to the exterior surface of the inner catheter; and a second of the plurality of inner catheter lumens comprising at least one distal end-tip opening; the method comprising the steps of:
 directing the catheter assembly into proximity with a blood vessel; 
 further directing the inner catheter member through a wall of the blood vessel into a vessel lumen thereof, and further directing the outer sheath into close proximity with the blood vessel such that substantially none of the plurality of inner catheter apertures are open outside the blood vessel, said inner catheter apertures being open into the vessel lumen or sealingly covered by the outer sheath; 
 directing a first therapeutic agent through the first inner catheter lumen and at least one inner catheter aperture; and, 
 directing a second therapeutic agent through the second inner catheter lumen; 
 wherein the plurality of apertures comprises at least four apertures, the apertures being distributed around a circumference and along a length of the inner catheter; 
 wherein a more distal aperture of the plurality of apertures comprises a larger surface area than a surface area of a more proximal aperture such that the flow of the first therapeutic agent through the more distal aperture and the more proximal aperture is the same when the more distal aperture and the more proximal aperture are open into the vessel lumen; and, 
 wherein the plurality of apertures open into the vessel lumen provide for a low-level flow of the first therapeutic agent to deliver a minimum effective concentration of the first therapeutic agent to the exterior surface of the inner catheter. 
 
     
     
       2. The method of  claim 1  further comprising a step of aligning distal ends of the inner catheter member and the outer sheath. 
     
     
       3. The method of  claim 1  further comprising a step of directing a distal portion of the outer sheath into the blood vessel. 
     
     
       4. The method of  claim 3  further comprising a step of longitudinally adjusting the position of the inner catheter relative to the outer sheath in a manner controlling the number of apertures not covered by the outer sheath. 
     
     
       5. The method of  claim 1 , wherein the catheter is dimensioned for use as a central venous catheter, and the blood vessel is selected from one of a subclavian vein, a femoral vein, and a jugular vein. 
     
     
       6. The method of  claim 1 , wherein at least one of the therapeutic agents is an anti-thrombotic agent. 
     
     
       7. The method of  claim 1 , wherein each of a first sub-plurality of the apertures comprises a different surface area than each of a second sub-plurality of the apertures. 
     
     
       8. The method of  claim 1 , the catheter assembly further comprising a closed distal end-tip of the first of the plurality of inner catheter lumens such that the plurality of apertures is disposed only along lateral sides of the inner catheter, configured thereby to be sealingly covered by an inward surface of the at least one patent sheath lumen. 
     
     
       9. The method of  claim 1 , wherein the plurality of apertures comprises at least ten apertures. 
     
     
       10. The method of  claim 1 , wherein the plurality of apertures comprises at least twenty five apertures. 
     
     
       11. The method of  claim 1 , wherein each aperture of the plurality of apertures has a diameter between 0.1 mm to 1.0 mm. 
     
     
       12. The method of  claim 1 , wherein each aperture of the plurality of apertures has a diameter between 0.3 mm to 0.5 mm. 
     
     
       13. The method of  claim 1 , wherein the plurality of apertures are uniformly distributed around the circumference and along the length of the inner catheter. 
     
     
       14. The method of  claim 1 , wherein the plurality of apertures are non-uniformly distributed around the circumference and along the length of the inner catheter. 
     
     
       15. The method of  claim 1 , wherein a flow of the first therapeutic agent through the plurality of apertures open into the vessel lumen is consistent along a length of the inner catheter having the plurality of apertures open into the vessel lumen. 
     
     
       16. The method of  claim 1 , wherein the plurality of apertures are distributed along a length of at least 3 cm of the inner catheter. 
     
     
       17. The method of  claim 1 , wherein the plurality of apertures are distributed along a length of at least 6 cm of the inner catheter.